Random Shudder when slowing down from speed....

[jbray1984]

Hey guys,

Just been having this issue for the last few days now... When I'm above speeds of 110km/hour and go to slow down the whole car starts to shudder.. I thought maybe a wheel alignment might be in order?
Anyone shed some light on this for me?

 

[Wongy295]

Brake pads could be on the way out.

Rotors might need machining.

 

[jbray1984]

Even when not using the brakes though? Sorry I probably should have said it's not just when braking, as an example.. Speed up to say 130km/h then just let the throttle off and let it glide down... It starts to shudder.

 

[Alex05]

Could be a wheel balance issue or an alignment issue

 

[nickb1993]

Could be tailshaft balance

 

[jbray1984]

Could be tailshaft balance

That sounds bad lol...

 

[Wongy295]

Could be a wheel balance issue or an alignment issue

Yeah, second this. Cheapest check

 

[Sean880]

IMHO, if it was wheel balance or tailshaft balance or faulty tyres or a warped wheel on the car you would not ONLY get the vibration when coasting and decelerating. You should also notice it when the vehicle was under power and running the same speeds when the coasting vibration cuts in.
Out of balance wheels, for example, do not stop vibrating when you change from coasting to power. They are either out of balance and vibrating in particular speed ranges or they are balanced and not vibrating in those speed ranges.

(It is most unlikely that the vibration described when coasting/decelerating has anything to do with wheel alignment as such) .

Rotate the back wheels to the front and fronts to the rear and see if there is any difference. No harm in doing a re-balance of the wheels either but I doubt there will be any difference if the problem you described ONLY occurs when you are off the accelerator and the car is coasting/decelerating.

What work or modifications have you had done on the car recently, if any?

 

[jbray1984]

Nah all I've done is added subs. The issue was happening before I changed the tension pulleys in the engine.

But wasn't happening last week.

 

[greenacc]

I seem to remember a similar thread from a member in the usa recently. Could be caused by worn bushes in suspension or steering